1. Field of the Invention
The present invention relates to novel organic silicon compounds, hydrolyzates thereof, and rubber plasticizers comprising the same. More particularly, it relates to novel organic silicon compounds and hydrolyzates thereof which are useful as rubber plasticizers having improved properties including low volatility, non-extractability, and thermal aging and low-temperature resistance improvements in combination with modern advanced rubber articles on which high performance demand is imposed.
2. Prior Art
In the prior art, polyester plasticizers are most often used with rubber articles. Such polyester plasticizers are generally liquid polyesters prepared by dehydration condensation between a double alcohol terminated glycol and an aliphatic monobasic acid, usually having a viscosity of about 10 to about 7,000 centipoise. They are widely used with synthetic rubbers such as acrylonitrile-butadiene rubbers (NBR), chloroprene rubbers (CR), acrylic rubbers (ACM and ANM) and fluoride rubbers (FKM) for providing plasticity and particularly, improved low-temperature resistance thereto.
However, during long term service of rubber articles in hot oil, these polyester plasticizers tend to be extracted with and migrate into hot oil, failing to take advantage of their low-temperature resistance improving facility. Extraction and migration of polyester plasticizers into hot oil may be somewhat controlled by increasing the molecular weight of polyester plasticizers at the expense of efficient plasticization and low-temperature resistance improvement.
Although the polyester plasticizers insure improved physical properties to vulcanized rubbers, their drawbacks are serious as described above. There is a need for a plasticizer which is non-extractable, efficient in plasticization, and effective in improving low-temperature resistance when used with rubber.